Can a disconnect switch be installed at the bottom of the subpanel and under/below all control components/circuits?

[petersonra]

I never understood the point of an integral disconnecting means.

There will always be power available on the line side of the control cabinet disconnect regardless of whether the disconnect is off unless you lock out the source.

Much like line side power to a shunt trip breaker on an MDP fed directly from a utility transformer.

Thousands of control cabinets are set up this way.

The disconnecting means in the control panel itself does not disconnect the power inside the enclosure.

JAP>

You need to understand that the disconnecting means to a control panel disconnects power for everything that the panel controls. And that's its intent. It's not intended to disconnect power to the control panel. That way you don't have to have disconnect switches on every freaking motor The control panel controls. Most of the time when you have a control panel like this if you have to shut off one motor you might as well just shut down the whole machine until you get it fixed. And it's also a good place to lock out the whole machine if you need to work on the machine. You don't have to go out and put 17 lock outs on to do some repair.

 

[jap]

I'm just saying there are times when the controller itself needs to be worked on. An external diconnect at the controller location instead of an integral is much more handy.


Jap>

 

[tom baker]

Reading through the posts, is this a large control panel with multiple component, contractors, vfds etc? And is attached to a skid? Is the control panel UL 508B listed?

 

[Dsg319]

Possibly vice/versa in your situation.
As in control cabinet over your disco.

 

[petersonra]

Just as anything else, most of the hidden dangers are dependent on the caliber of the electrician doing the actual wiring.

JAP>

Certainly there are dangers from the level of competence involved in the person working on anything. Not sure what that has to do with the design decision on where to locate a component inside a control panel.

 

[petersonra]

I'm just saying there are times when the controller itself needs to be worked on. An external diconnect at the controller location instead of an integral is much more handy.


Jap>

That's true, but a separate issue.

 

[jap]

Certainly there are dangers from the level of competence involved in the person working on anything. Not sure what that has to do with the design decision on where to locate a component inside a control panel.

The OP is talking about the location of a panel disconnect, not the location of a component inside the panel.
Mentioned in post 19 if the DS has 480 on it it's likely other items do also.
There shouldn't be if the disconnect is off.
Only voltage on the line side of the DS unless there's an external source entering the cabinet that doesn't get disconnected through the disconnect.

JAP>

 

[tom baker]

Like I asked, this may be a big panel supplied by skid mfg and they put the disconnect at the bottom, A picture would help.

 

[jap]

View attachment 2556861 Possibly vice/versa in your situation.
As in control cabinet over your disco.

This is a code section that deals with working space clearances.

The OP's question/concern was about foreign objects falling into a bottom mounted face up rotary disconnect in a control cabinet (which to my knowledge is not a code violation), much like the concern of something falling into a receptacle installed in a dwelling unit counter top ( which IS a code violation),,,,, only on a much larger scale.

JAP>

 

[Dsg319]

This is a code section that deals with working space clearances.

The OP's question/concern was about foreign objects falling into a bottom mounted face up rotary disconnect in a control cabinet (which to my knowledge is not a code violation), much like the concern of something falling into a receptacle installed in a dwelling unit counter top ( which IS a code violation),,,,, only on a much larger scale.

JAP>

Ah, I misunderstood. Probably didn’t read enough of the post.